Respiratory Support Effects over Time on Regional Lung Ventilation Assessed by Electrical Impedance Tomography in Premature Infants.

Background and objectives: Respiratory distress syndrome (RDS) frequently necessitates respiratory support. While non-invasive methods are typically the preferred approach, mechanical ventilation becomes necessary for patients with insufficient response. Our study aimed to compare two common respiratory support modes, volume-targeted mechanical ventilation and non-invasive ventilation continuous positive airway pressure (CPAP) and high-flow nasal cannula (HFNC), using electrical impedance tomography. Materials and Methods: Infants with very low birth weight and gestational ages of less than 32 weeks were eligible for inclusion in the study. All enrolled infants were beyond the transitional period (>72 h of age). The infants were divided into two groups: infants receiving invasive respiratory support through an endotracheal tube and infants receiving non-invasive respiratory support. We used electrical impedance tomography to assess end-expiratory lung impedance (EELZ), DeltaZ, heterogeneity, and regional ventilation distribution. Patients were evaluated at 0, 30, and 60 min after assuming the supine position to examine potential time-related effects. Results: Our study initially enrolled 97 infants, and the final analysis included a cohort of 72 infants. Ventilated infants exhibited significantly larger EELZ compared to their non-invasive counterparts (p = 0.026). DeltaZ was also greater in the invasive respiratory support group (p < 0.001). Heterogeneity was higher in the non-invasive group and did not change significantly over time. The non-invasive group demonstrated significantly greater ventilation in the dependent lung areas compared to intubated patients (p = 0.005). Regional distribution in the left lung was lower than in the right lung in both groups; however, this difference was significantly more pronounced in intubated patients (p < 0.001). Conclusions: Our study revealed that volume-targeted mechanical ventilation results in higher EELZ and DeltaZ compared to spontaneously breathing infants receiving non-invasive respiratory support. However, lung heterogeneity was lower during mechanical ventilation. Our study also reaffirmed that spontaneous breathing promotes greater involvement of the dependent lung compared to mechanical ventilation.

Noninvasive Respiratory Support Effects on Sighs in Preterm Infants by Electrical Impedance Tomography.

OBJECTIVE: To evaluate differences regarding sigh frequency between noninvasive respiratory support types and to assess regional ventilation distribution, delta Z, and end-expiratory lung impedance differences before and after sighs. METHODS: Very low-birth-weight infants with gestational ages less than 32 wk were included in the study. Participants were split into two groups: those receiving continuous positive airway pressure and infants receiving high-flow nasal cannula therapy. RESULTS: The study enrolled 30 infants. The high-flow nasal cannula therapy group had more sighs per 10-min period than infants receiving continuous positive airway pressure (p = 0.016). Ventilation distribution was similar in the anterior and right ventilation distribution compartments pre- and post-sigh (46.30% vs. 45.68% and 54.27% vs. 55.26%, respectively). No statistically significant increase in end-expiratory lung impedance or delta Z was observed in global or separate lung regions (p > 0.05). CONCLUSION: The study has demonstrated that sighs are more frequent in infants receiving high-flow nasal cannula respiratory support compared to continuous positive airway pressure. Spontaneously occurring sighs on noninvasive respiratory support due to respiratory distress syndrome (RDS) do not increase end-expiratory lung impedance or alter delta Z, and appear to have limited clinical significance. TRIAL REGISTRATION: Prospectively registered at www. CLINICALTRIALS: gov , reg. No. NCT04542096, reg. date 01/09/2020.

Impact of Medical Treatment of Hemodynamically Significant Patent Ductus Arteriosus on Cerebral and Renal Tissue Oxygenation Measured by Near-Infrared Spectroscopy in Very Low-Birth-Weight Infants.

Background and objective: Hemodynamically significant patent ductus arteriosus (hsPDA) can cause ductal steal and contribute to poor outcomes in preterm infants. Near-infrared spectroscopy (NIRS) allows us to continuously evaluate regional tissue oxygenation (rSpO2) and perfusion changes in underlying organs. The aim of this study was to evaluate the effect of medical treatment for hsPDA on cerebral and renal rSpO2 in infants less than 32 weeks of gestational age, and older than 72 h of life. Materials and methods: Infants with a gestational age of <32 weeks with hsPDA were prospectively studied before and during medical treatment. Two-site (cerebral and renal) rSpO2 monitoring by NIRS was performed 1 h before treatment (T0) and 24 h (T1), 24−48 h (T2), 48−72 h (T3) after the infusion of the first drug dose. Results: A total of 21 infants were studied. The mean day of life at treatment initiation was 8.2 (SD, 2.75). The DA diameter, LA/Ao ratio, and resistive index in the anterior cerebral artery (RI ACA) were significantly lower after treatment (p < 0.05). There were no significant differences in cerebral rSpO2, cerebral fractional tissue oxygen extraction (FTOE), and SpO2 comparing different time points. A significantly higher renal SpO2 value was recorded at T2 as compared with T0 (75.0%, SD 4.9%, vs. 69.4%, SD 7.6%; p < 0.013), while for renal FTOE, a tendency to lower values at T2 was observed (0.18, SD 0.05, vs. 0.24, SD 0.09; p = 0.068). Conclusions: Late (later than 7 days postpartum) hsPDA medical treatment with paracetamol or ibuprofen completely closed the duct only in a small proportion of preterm infants, despite a statistically significant reduction in the DA diameter, LA/Ao ratio, and RI ACA. Continuous renal, not cerebral, NIRS measurements can help to anticipate the efficacy of medical treatment of hsPDA in preterm infants. Large-scale prospective studies are needed to ascertain that renal and cerebral NIRS can be used as a reliable tool for evaluating the effectiveness of medical treatment for hsPDA.

Acute paediatric kidney replacement therapies in Europe: demographic results from the EurAKId Registry.

BACKGROUND: Acute kidney injury (AKI), particularly that requiring dialysis, is a severe complication in hospitalized children that is associated with high morbidity and mortality. A prospective European AKI registry (EurAKId registry, NCT02960867) was created to describe the epidemiology and outcomes of paediatric patients treated with acute dialysis. METHODS: Children were recruited who were between 0 and 18 years of age and were treated both in and outside the paediatric intensive care unit (PICU) with peritoneal dialysis (PD), haemodialysis (HD) or continuous kidney replacement therapy (CKRT) for AKI or metabolic derangement, fluid overload (FO), sepsis or respiratory distress. Five age groups and 12 categories of primary diseases were defined. RESULTS: Data on 340 patients were analysed, of whom 86% received dialysis for AKI and 14% for reasons other than AKI. Boys accounted for 60% of the patients. Illness severity was greater in children with cardiac and haematologic diseases than those with kidney diseases. Most patients received dialysis in the PICU (84%). The most frequently used dialysis modality was CKRT (64%), followed by PD (14%) and HD (14%). The overall survival rate was 65%. Survival was significantly lower in children with three comorbidities than in children with no comorbidities (41% and 83%; P < 0.001). CONCLUSIONS: The EurAKId registry is the first prospective registry considering paediatric acute kidney replacement therapies (KRTs) in both critical and non-critical care settings, focusing on the three dialysis modalities in Europe. The clinical indications for KRT have expanded; our population was characterized by critically ill patients, primarily boys, who frequently received dialysis in the PICU with CKRT.

Brain and renal oxygenation measured by NIRS related to patent ductus arteriosus in preterm infants: a prospective observational study.

BACKGROUND: Patent ductus arteriosus (PDA) is common among preterm neonates. Haemodynamically significant ductus arteriosus (hsPDA) can cause ductal steal and contribute to poor outcomes. Our aim was to evaluate ductus arteriosus patency and significance using two-site near-infrared spectroscopy (NIRS) measurements in preterm infants older than 72 h as a supplemental tool to echocardiography. METHODS: In this prospective observational study, 123 preterm infants (gestational age (GA) < 32 weeks, birth weight < 1500 g) were enrolled. Sixty-four newborns had closed ductus arteriosus (noPDA), and 41 and 18 patients were assigned to the PDA and hsPDA groups, respectively, per predefined echocardiographic criteria. Cerebral and renal oxygenation were assessed during NIRS monitoring. RESULTS: A higher renal mean (±SD) regional tissue oxygen saturation (rSpO2) (76.7 (±7.64)) was detected in the noPDA group than in the PDA (71.7 (±9.02)) and hsPDA (67.4 (±13.48)) groups (p < 0.001). Renal fractional tissue oxygen extraction (FTOE) (0.18 (±0.079)) was lower in the noPDA group than in the PDA (0.23 (±0.092)) and hsPDA (0.24 (±0.117))0.117 groups (p = 0.002). Cerebral oxygenation was significantly lower in the hsPDA group (77.0 (±5.16)) than in the noPDA (79.3 (±2.45)) and PDA (79.7 (±2.27)) groups (p = 0.004). There was no significant difference in cerebral fractional tissue oxygen extraction (FTOE) between any of the groups. CONCLUSIONS: Our results suggest that renal oxygenation is affected by ductus patency in preterm infants older than 72 h. Significant differences in cerebral oxygenation were observed between the hsPDA group and the PDA and noPDA groups. TRIAL REGISTRATION: ClinicalTrials.gov Identifier: NCT04295395. Registration date: 4 March 2020. This study was retrospectively registered, https://clinicaltrials.gov/ct2/show/NCT04295395 .

Congenital methemoglobinemia: Rare presentation of cyanosis in newborns.

Methemoglobin (MetHb) is an oxidized form on hemoglobin, which is unable to bind oxygen and consequently carry it to the tissues. Normally present in small quantities (<1%) without detrimental effects, its elevation produces hypoxemia which can be profound and even lethal. Methemoglobinemia is an abnormal increase of MetHb (>3%) of total hemoglobin. It can be classified in two types: hereditary and acquired. Acquired form is caused by exogenous oxidizing agents, such as nitrites or certain medications, while hereditary types of disease are the result of genetic deficiency in cytochrome B5 reductase, an enzyme responsible for MetHb reduction to hemoglobin. Little data is available on the epidemiology of methemoglobinemia. In general population only sporadic cases are described, while some isolated ethnic populations have increased incidence, possibly inherited from a common ancestor. We present a case of congenital methemoglobinemia in which detection of MetHb was hampered by faulty initial blood gas spectrometry results. A short literature review is also included.

Renal Replacement Therapy in Children in Lithuania: Challenges, Trends, and Outcomes.

Background and Objectives: Pediatric renal replacement therapy (RRT) in Lithuania resumed in 1994 after a 12-year pause in renal transplantation. Management of end stage renal disease (ESRD) has changed, and outcomes have improved over decades. Our aim was to evaluate the dynamics of RRT in Lithuania in the period 1994⁻2015, describe its distinctive features, and compare our results with other countries. Materials and Methods: Data between 1994 and 2015 were collected from patients under the age of 18 years with ESRD receiving RRT. The data included: Hemodialysis (HD), peritoneal dialysis (PD), transplantation incidence and prevalence, transplant waiting time, dialysis modalities before transplantation, causes of ESRD and gender distribution in transplanted patients, and patient and graft survival. Results: RRT incidence and prevalence maintained an increase up until 2009. Sixty-four transplantations were performed. Juvenile nephronophthisis (25.9%) was the primary cause of ESRD in transplanted children. The transplant waiting time median was 8.0 months. The male to female ratio post-transplantation was 1.02. Patient survival after transplantation at 10 years was 90.0%, while graft survival for living (related) was 77.0% and 51.1% for deceased. Twelve patients died while on RRT. Conclusions: RRT numbers are increasing in Lithuania. HD is the primary treatment of choice before transplantation, with continued low numbers of preemptive transplantation. Patient survival post-transplantation is favorable, though graft survival is less satisfactory.